DMN: SMU earthquake, drilling findings are years off

DMN: SMU earthquake, drilling findings are years off

Journalist James Osborne with the Dallas Morning News covered the research of SMU seismologist Heather R. DeShon.

DeShon is leading the effort to trace the source of a recent sequence of small earthquakes in North Texas and any relationship they may have to the injection of waste water by energy companies using shale gas production to recover gas.

North Texas earthquakes occurring in the Reno-Azle area since Nov. 5, 2013, and in Mineral Wells since Nov. 28, 2013, have raised scientific questions about the nature of these sequences and heightened local and national concerns about the impact of shale gas production on infrastructure and subsurface structures.

DeShon, an associate professor of geophysics, is an expert in earthquake generation within subduction zones and intraplate settings, seismogenic zone processes, local earthquake tomography and volcano seismology.

By James Osborne
Dallas Morning News
Scientists at SMU studying the earthquakes around Azle warned Friday that it would be years before they were able to determine a possible link to nearby natural gas drilling.

Heather DeShon, the geophysics professor leading the team, said seismographs deployed around the epicenter of the activity would remain in place for 6 to 12 months. Peer-reviewed analysis could take years more.

“It is important we do not rush to conclusions,” she said at a news conference Friday. “I understand people want results quickly. But we have to sit and wait a little while.”

The study aims to determine whether injection wells used by the natural gas drilling industry to pump vast volumes of wastewater underground caused the earthquakes. Seismic activity in other states has been linked by scientists to injection wells.

There are three injection wells within a 6-mile radius of the center of the seismic activity, DeShon said. But whether any of those wells cross the underground faults that drive seismic activity is unknown.

Brian Stump, a seismologist at SMU, said scientists long ago established an older and historically inactive fault line running close to Azle and Mineral Wells. But the exact path of the fault is unknown, and scientists are curious about whether other smaller faults might be present.

“These aren’t active faults like on a plate boundary,” Stump said. “But these faults do have stress on them.”

The research is funded by SMU using equipment on loan from the U.S. Geological Survey and a consortium of U.S. universities. A spokeswoman for the university said the study would receive no funding from the oil and gas industry.